Perimeter Calculator
Calculate the perimeter of squares, rectangles, triangles, circles and more. Get accurate perimeter measurements for any shape instantly.
Perimeter Calculator
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Understanding Perimeter
What is Perimeter?
Perimeter is the total distance around a two-dimensional shape. It's calculated by adding up the lengths of all the sides of the shape.
Perimeter vs. Area
While perimeter measures the distance around a shape, area measures the space inside the shape. Both are important in geometry.
Perimeter Formulas
- Square: P = 4 × side
- Rectangle: P = 2 × (length + width)
- Triangle: P = side1 + side2 + side3
- Circle (Circumference): P = 2 × π × radius
- Regular Polygon: P = number of sides × side length
Practical Applications
- Calculating fencing needed for a yard
- Determining trim length for a room
- Measuring the boundary of sports fields
- Planning garden borders
- Estimating materials for construction projects
Perimeter FAQs
What's the difference between perimeter and circumference?
Perimeter is the general term for the distance around any closed shape, while circumference specifically refers to the perimeter of a circle. The formula for circumference is 2πr (where r is the radius), which is unique to circles.
How do you find perimeter of irregular shapes?
For irregular shapes, simply add up the lengths of all the sides. If some sides are missing measurements, you may need to use other geometric properties or trigonometry to find those lengths first.
Why is perimeter important in real life?
Perimeter calculations are essential for many practical applications like construction (determining how much material is needed for borders), landscaping (calculating fence lengths), and manufacturing (measuring material requirements).
How does perimeter relate to area?
While perimeter measures the boundary length, area measures the space enclosed. Shapes can have the same perimeter but different areas (like a long thin rectangle vs. a square). Understanding both helps in optimizing space and material usage.